To make sure I get you the right information, could you clarify if you are referring to:

: A specific text file containing roughly 258,000 English/Canadian English words used for spell-checking or dictionary research?

It sounds like you're looking for a specific or document often referenced in academic papers or technical projects, but the query is a bit broad.

: A specific study that uses a "258K CANADA" dataset for Natural Language Processing (NLP) or machine learning ?